SouthCoast Wind
Lease area OCS-A 0521 (formerly Mayflower Wind), ~45 km south of Nantucket. Ocean Winds (OW North America) acquired 100% ownership.
Status
On Holdlifecycle stage
FragileHafrok completion outlook
Ownership
Ocean Winds — 100% ◆Location
United StatesNorthwest Atlantic
Technology
Capacity
2,400 MW ◇
Turbines
—
Foundation
—
Site & conditions
Site rights
Seabed rights held ∴
Origination
BOEM Massachusetts Lease Sale (ATLW-4A) · 2018 ·
Water depth
38–62 m ≈
Wind speed
10.2 m/s @ 150 m ≈
Revenue & grid
Offtake
Other ◇
Grid
—
Schedule
FID
Not taken
COD · Hafrok
—
Delivery outlook modelled by Hafrok · calibrated on delivered projects
—
on hold — no credible date; the chart shows when a restarted project might complete
Chance of delivery
≈6%
estimated chance this project reaches commercial operation
Projects put on hold complete ≈15% of the time on Hafrok's record. This one sits well below that: a market with a thinner delivery record, a very large build, technical complexity and no offtake contract yet. Only a restart would change that — there is no dated schedule to judge against. That figure is then halved while Hafrok reads the United States route as closed: a route that has to be won again is less likely to be won.
COD outlook
If it completes, when — Hafrok’s probability by year (teal)
| Year | Probability |
|---|---|
| 2033 | 20.0% |
| 2034 | 20.0% |
| 2035 | 20.0% |
| 2036 | 20.0% |
| 2037 | 20.0% |
How Hafrok got this date
1
On hold — no dated schedule
The project is recorded as On Hold, so no sequence of milestones can be trusted. Hafrok publishes no expected year; the chart instead spreads the remaining chance of completion over the years a restarted project might finish in.
2
Route closed until 2029
Hafrok believes a held project in the United States is unlikely to resume before a route to build exists again, and does not expect one before
January 2029. On that reading the years the chart spreads the remaining chance over begin after 2029, not after today. This is Hafrok's judgment, not a fact on the record — what it rests on: United States market page.3
Chance of delivery — separate from timing
Start from the share of On Hold projects that went on to complete — ≈15%, measured on Hafrok's record of delivered and abandoned projects, with an allowance held back where that record cannot yet speak (projects still unresolved, changed market conditions). Historically only a minority of projects put on hold returned to delivery — the estimate reflects that. Then adjust for this project's own evidence — offtake, market, size, technical complexity — and halve the result while Hafrok reads the United States route as closed (a route that has to be won again is less likely to be won) — to ≈6%, which rates it
Fragile on Hafrok's four-step delivery scale (Delivering · Expected · Prospective · Fragile).Project timeline & ownership verified milestones on the spine · ownership from Hafrok’s transactions record
Origination · 2018-12
BOEM Massachusetts Lease Sale (ATLW-4A)
- Awarded to
- Mayflower Wind Energy, LLC
- Lease
- OCS-A 0521
- Basis
- seabed award
Founding JV · 2018-12
EDP Renewables · Shell — On 13–14 December 2018, BOEM held a competitive lease sale offshore Massachusetts. Mayflower Wind Energy LLC — a newly formed 50/50 JV between EDPR Offshore North America LLC (EDP Renewables) and Shell New Energies US LLC — was the provisional winner of Lease Area OCS-A 0521 (127,388 acres, potential capacity ~1.6 GW). Mayflower bid USD 135 million for the lease (USD 135m × 0.89 = EUR 120.4m). At the time of auction ENGIE was not yet a partner; Ocean Winds (the EDPR/ENGIE 50/50 JV) was created in 2019 and eventually became the EDPR vehicle for the project, but Shell and Ocean Winds were described as 50/50 owners.
Evidence
- unknown — SouthCoast Wind (formerly Mayflower Wind) | Bureau of Ocean Energy Management ↗ ◆ held
- globenewswire.com — Shell and EDP Renewables joint venture wins offshore wind ↗ 2018-12 ◆ held
- offshoreWIND.biz ↗ ◆ held
From the auction results — the round that created the project; founding JV from Hafrok’s transactions record.
Divestment · 2024-03
Shell → Ocean Winds 50%
- Stake
- 50%
- Consideration
- not disclosed
- Announced
- 2024-03
- Project stage
- early development
In March 2024, Shell New Energies US LLC sold its 50% equity share in SouthCoast Wind Energy LLC to joint venture partner Ocean Winds North America LLC. The transaction signed and closed simultaneously with immediate effect. The sale consideration was not disclosed. Ocean Winds (an EDPR/ENGIE 50/50 JV) took full ownership of SouthCoast Wind and stated its intention to bring in a new 50% partner ahead of the final investment decision. BOEM approved the Construction and Operations Plan for the 2,400 MW project in December 2024. Note: this is a distressed exit; implied value likely well below typical pre-FID benchmarks.
Evidence
- Ocean Winds — Ocean Winds takes full ownership of SouthCoast Wind project ↗ 2024-03-21 ◆ held
- shell.us — Shell sells interest in SouthCoast Wind to existing joint venture partner, Ocean Winds | About Us ↗ 2024-03 ◆ held
- offshoreWIND.biz — Shell Exits US Offshore Wind Project, Sells Stake to Ocean Winds ↗ 2024-03 ◆ held
From Hafrok’s transactions record
Dashed tick marks today (9 Sep 2026). The teal diamond on the spine is origination — the seabed award or round that created the project. Every other ownership event lives in the band below: one station per recorded deal, dated at its label, in deal order rather than to calendar scale. Secondary trades appear only at the interchanges; grey lines are parties whose entry or exit Hafrok’s record does not hold.
Revenue & offtake contract duration and price levels · money of the day
2,491 MW contracted — utility PPA
● Utility PPA · Massachusetts Section 83C Round 2 terminated
Price$58.47/MWh ·Capacity804 MWAwardedOct 2019● Utility PPA · Massachusetts Section 83C Round 3 terminated
Priceprice undisclosed ·Capacity400 MWAwardedDec 2021● Utility PPA · New England Multi-State Offshore Wind Solicitation (MA + RI)
Priceprice undisclosed ·Capacity1,287 MWAwardedSep 2024Installation how the build is going · from satellite counts and Hafrok’s registers
Installation not started
nothing to count yet: the satellite tracker begins when offshore construction does
Installation · on record
StageOn Hold
Offshore constructionnot started
Expected start of operationnot stated
Sources & verification
2/10 fields verified · rests on 12 sources (3 primary) · ◆ 7 documents held
◆Verified≈Modelled◇Sourced∴Inferred⌁Convention○Unverified∅No source·Derived
Numbers are stable citation ids — grouped by source class, so they are not consecutive.
Regulator3
[4]
[9]
Bureau of Ocean Energy Management (BOEM)2026-08-23◆ US BOEM offshore-wind register (FR docum…
“Lease row OCS-A 0521: companies ['SouthCoast Wind Energy LLC']; lease_dates ['04/01/2019']; lease_terms ['33 Years']; states ['Massachusetts']; block_count 193.”
supportsRegister entry
[10]
Bureau of Ocean Energy Management (BOEM)2026-08-23◆ SouthCoast Wind (formerly Mayflower Wind…
“On January 17, 2025, BOEM announced the approval of the SouthCoast Wind Project Construction and Operations Plan (COP), as modified by the selected alternative in the Record of Decision.”
supportsConsentConsent granted
Auction results3
[11]
MA DOER / EDCs2019◆ us-ma-83c-r2
Massachusetts 83C Round 2 RFP - Mayflower/SouthCoast (terminated/repriced 2023-24).
supportsUtility PPA · Massachusetts Section 83C Round 2
[12]
MA DOER / EDCs2021◆ us-ma-83c-r3
Massachusetts 83C Round 3 RFP - Commonwealth Wind (Avangrid terminated 2023).
supportsUtility PPA · Massachusetts Section 83C Round 3
[13]
MA DOER & EDCs + RI + CT2023◆ us-ma-83c-r4
Massachusetts/multi-state 83C Round 4 RFP (MA/RI/CT coordinated, up to 3,600 MW).
supportsUtility PPA · New England Multi-State Offshore Wind Solicitation (MA + RI)
Trade press5
[3]
offshoreWIND.biz2024-03◆ Shell Exits US Offshore Wind Project, Se…
Press report — cited, not quoted; read it at the source link.
supportsoperator
[5]
[6]
[7]
[8]
Unverified import1
[1]
unknown◆ SouthCoast Wind (formerly Mayflower Wind…
supportsTotal capacityWater depthCoordinates